'Fingerprints' match molecular simulations with reality

As a molecule jumps between structural states (below), it creates ''dynamical fingerprints'' (top spectra) that can tie together high-performance simulation and experiments.

As a molecule jumps between structural states (below), it creates ''dynamical fingerprints'' (top spectra) that can tie together high-performance simulation and experiments.

A theoretical technique developed at the Department of Energy's Oak Ridge National Laboratory is bringing supercomputer simulations and experimental results closer together by identifying common "fingerprints."

ORNL's Jeremy Smith collaborated on devising a method -- dynamical fingerprints --that reconciles the different signals between experiments and computer simulations to strengthen analyses of molecules in motion. The research will be published in the Proceedings of the National Academy of Sciences.

"Experiments tend to produce relatively simple and smooth-looking signals, as they only 'see' a molecule's motions at low resolution," said Smith, who directs ORNL's Center for Molecular Biophysics and holds a Governor's Chair at the University of Tennessee. "In contrast, data from a supercomputer simulation are complex and difficult to analyse, as the atoms move around in the simulation in a multitude of jumps, wiggles and jiggles. How to reconcile these different views of the same phenomenon has been a long-standing problem."

The new method solves the problem by calculating peaks within the simulated and experimental data, creating distinct "dynamical fingerprints." The technique, conceived by Smith's former graduate student Frank Noe, now at the Free University of Berlin, can then link the two datasets.

Supercomputer simulations and modeling capabilities can add a layer of complexity missing from many types of molecular experiments.